I just got my for CPS2 A and B boards (SSF2 phoenixed) and am really enjoying it. The only problem I've having, though, is the sound is set to max volume when it is first powered up. I can adjust the volume and it works fine, and I can power off the machine for a couple minutes, turn it back on, and the volume has retained its settings. If I leave the machine off for several minutes (haven't timed exactly, but I've tried like an hour later) the volume has reset itself and is back to the highest setting. I'm now used to having to open my cab up to adjust the volume before playing it now, but it's kind of annoying. Is there some type of battery in the A board that retains that setting that I can swap out, or is this just how CPS2 works? Thanks.

The sound sounds perfectly fine. It keeps the volume setting if I cycle power within a few minutes, but if I turn the machine on an hour later, the sound is back at full volume. It's not a major problem, it just freaks me out every time I forget to adjust it when first powering on. This is the only A board I've got at the moment, so can't swap one out just yet.

its important to note what kernow said about other settings,set you coin settings at a non standard amount and see if they reset as well
likely to be a battery in the motherboard imo
easy to prove,open up the the a board and meter the battery after 2 hours on non operation

Woops. Yes, it does keep all other settings like freeplay, coins, difficulty, etc. I opened the A board and the wires attached to the volume up look kind of shoddy, and one of the wires is soldered on to two points, but it looks like those traces are connected anyway. I'll probably just redo the wiring for the volume buttons and see if that helps. The volume down and test connections look ok.

CPS2 board do sometimes 'lose' their volume settings, but it usually shows as the volume being too low and not adjustable - the solution to that is to hold down the volume down button when you power on until the the splash screen appears. You cvould try that and see if t makes any difference.

I mainly mention this in case it's related - it does seem strange that the other data is being retained on your board, so perhaps something else is going on in that circuit - maybe a bad electrolytic cap for example as was suggested further up this thread.

I would think this is stored in an SRAM or NVRAM on the mainboard. It's possible that it is broken, but very unlikely. Did you restore factory defaults yet using test menu?
What happens when you swap in another game board, does the volume stick as well?

This issue might be related to the low volume audio issue mentioned above by VectorGlow, just manifesting itself in a different manner.

On the A-board PCB, there are two Toshiba chips. They control the audio volume and seem to be very sensitive to conductive dust. You should clean the dust off thoroughly with an anti-static PCB brush which can be found on eBay quite cheaply. This may resolve the issue.

If the problem persists, try replacing the supercap. This is the component that people often mistake for a battery. To clarify, there is no battery in the A-board.

If neither of the above two possible solutions fix problem, then the fault probably lies elsewhere.

Hi idc, thanks, have cleaned the whole board already but will give those Toshiba ICs another thorough clean. Had also replaced the super cap. The 1st Toshiba IC(don't know the part from the top of my head) does get power from the super cap.

The real problem is the supercap. Happens when it doesn't keep the charge.

Actually, the board is designed to boot on the maximum volume if the capacitor discharges completely. When the discharge isn't complete, the capacitor might have a low voltage, which isn't high enough to allow the chip to work or not low enough to cause it to reset, you have a glitch.

Try shorting the supercap with a wire. (connect the wire to both sides of the cap. it looks like a battery) Then, try the A board again.

That fix is only for early A boards. Later ones come with the fix already incorporated on the circuitry.

It's meant to prevent glitches during power transitions. Glitches which could corrupt the bigger toshiba chip (panel/buttons controller) RAM and make it upload weird settings into the actual volume control chip (the smaller toshiba chip).

One I have has this fix from factory. It has the code 93646A-4 printed on the solder mask and the chips have date codes near to yours (93 week 44, for example) meaning it was produced a couple weeks later than yours.

I have an A board that, when powered off for a minute or so, kept resetting the volume back to a low volume (but not zero). I tried the "power on with volume down held in" fix, etc but no luck ....... at first. NOW though the volume level is resetting to maximum after the unit has been powered off for a minute or so.

I've looked through this thread and see the supercap mentioned, however other system and game settings are being retained just fine so the supercap must be okay, the EEPROM in that case should also be fine.

The wire mod fix doesn't seem to apply to this (later?) A board as pin 14 of the mentioned HC04 is already linked to D3 (but not lifted and done via a jumper wire mod, it's factory made that way and the layout of that area differs to the PCB photo in this thread).

The same B board works fine with another A board that doesn't have the issue.

Any other ideas please as to a fix for this volume level resetting issue?